aboutsummaryrefslogtreecommitdiffstats
path: root/net/netlabel/netlabel_cipso_v4.c
blob: 743b05734a497598feea4ca8dd609ad33ed276bf (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
/*
 * NetLabel CIPSO/IPv4 Support
 *
 * This file defines the CIPSO/IPv4 functions for the NetLabel system.  The
 * NetLabel system manages static and dynamic label mappings for network
 * protocols such as CIPSO and RIPSO.
 *
 * Author: Paul Moore <paul.moore@hp.com>
 *
 */

/*
 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
 *
 * This program is free software;  you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY;  without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 * the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program;  if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include <linux/types.h>
#include <linux/socket.h>
#include <linux/string.h>
#include <linux/skbuff.h>
#include <linux/audit.h>
#include <net/sock.h>
#include <net/netlink.h>
#include <net/genetlink.h>
#include <net/netlabel.h>
#include <net/cipso_ipv4.h>

#include "netlabel_user.h"
#include "netlabel_cipso_v4.h"

/* Argument struct for cipso_v4_doi_walk() */
struct netlbl_cipsov4_doiwalk_arg {
	struct netlink_callback *nl_cb;
	struct sk_buff *skb;
	u32 seq;
};

/* NetLabel Generic NETLINK CIPSOv4 family */
static struct genl_family netlbl_cipsov4_gnl_family = {
	.id = GENL_ID_GENERATE,
	.hdrsize = 0,
	.name = NETLBL_NLTYPE_CIPSOV4_NAME,
	.version = NETLBL_PROTO_VERSION,
	.maxattr = NLBL_CIPSOV4_A_MAX,
};

/* NetLabel Netlink attribute policy */
static struct nla_policy netlbl_cipsov4_genl_policy[NLBL_CIPSOV4_A_MAX + 1] = {
	[NLBL_CIPSOV4_A_DOI] = { .type = NLA_U32 },
	[NLBL_CIPSOV4_A_MTYPE] = { .type = NLA_U32 },
	[NLBL_CIPSOV4_A_TAG] = { .type = NLA_U8 },
	[NLBL_CIPSOV4_A_TAGLST] = { .type = NLA_NESTED },
	[NLBL_CIPSOV4_A_MLSLVLLOC] = { .type = NLA_U32 },
	[NLBL_CIPSOV4_A_MLSLVLREM] = { .type = NLA_U32 },
	[NLBL_CIPSOV4_A_MLSLVL] = { .type = NLA_NESTED },
	[NLBL_CIPSOV4_A_MLSLVLLST] = { .type = NLA_NESTED },
	[NLBL_CIPSOV4_A_MLSCATLOC] = { .type = NLA_U32 },
	[NLBL_CIPSOV4_A_MLSCATREM] = { .type = NLA_U32 },
	[NLBL_CIPSOV4_A_MLSCAT] = { .type = NLA_NESTED },
	[NLBL_CIPSOV4_A_MLSCATLST] = { .type = NLA_NESTED },
};

/*
 * Helper Functions
 */

/**
 * netlbl_cipsov4_doi_free - Frees a CIPSO V4 DOI definition
 * @entry: the entry's RCU field
 *
 * Description:
 * This function is designed to be used as a callback to the call_rcu()
 * function so that the memory allocated to the DOI definition can be released
 * safely.
 *
 */
static void netlbl_cipsov4_doi_free(struct rcu_head *entry)
{
	struct cipso_v4_doi *ptr;

	ptr = container_of(entry, struct cipso_v4_doi, rcu);
	switch (ptr->type) {
	case CIPSO_V4_MAP_STD:
		kfree(ptr->map.std->lvl.cipso);
		kfree(ptr->map.std->lvl.local);
		kfree(ptr->map.std->cat.cipso);
		kfree(ptr->map.std->cat.local);
		break;
	}
	kfree(ptr);
}

/**
 * netlbl_cipsov4_add_common - Parse the common sections of a ADD message
 * @info: the Generic NETLINK info block
 * @doi_def: the CIPSO V4 DOI definition
 *
 * Description:
 * Parse the common sections of a ADD message and fill in the related values
 * in @doi_def.  Returns zero on success, negative values on failure.
 *
 */
static int netlbl_cipsov4_add_common(struct genl_info *info,
				     struct cipso_v4_doi *doi_def)
{
	struct nlattr *nla;
	int nla_rem;
	u32 iter = 0;

	doi_def->doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);

	if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_TAGLST],
				NLBL_CIPSOV4_A_MAX,
				netlbl_cipsov4_genl_policy) != 0)
		return -EINVAL;

	nla_for_each_nested(nla, info->attrs[NLBL_CIPSOV4_A_TAGLST], nla_rem)
		if (nla->nla_type == NLBL_CIPSOV4_A_TAG) {
			if (iter > CIPSO_V4_TAG_MAXCNT)
				return -EINVAL;
			doi_def->tags[iter++] = nla_get_u8(nla);
		}
	if (iter < CIPSO_V4_TAG_MAXCNT)
		doi_def->tags[iter] = CIPSO_V4_TAG_INVALID;

	return 0;
}

/*
 * NetLabel Command Handlers
 */

/**
 * netlbl_cipsov4_add_std - Adds a CIPSO V4 DOI definition
 * @info: the Generic NETLINK info block
 *
 * Description:
 * Create a new CIPSO_V4_MAP_STD DOI definition based on the given ADD message
 * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
 * error.
 *
 */
static int netlbl_cipsov4_add_std(struct genl_info *info)
{
	int ret_val = -EINVAL;
	struct cipso_v4_doi *doi_def = NULL;
	struct nlattr *nla_a;
	struct nlattr *nla_b;
	int nla_a_rem;
	int nla_b_rem;

	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
	    !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST])
		return -EINVAL;

	if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
				NLBL_CIPSOV4_A_MAX,
				netlbl_cipsov4_genl_policy) != 0)
		return -EINVAL;

	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
	if (doi_def == NULL)
		return -ENOMEM;
	doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL);
	if (doi_def->map.std == NULL) {
		ret_val = -ENOMEM;
		goto add_std_failure;
	}
	doi_def->type = CIPSO_V4_MAP_STD;

	ret_val = netlbl_cipsov4_add_common(info, doi_def);
	if (ret_val != 0)
		goto add_std_failure;

	nla_for_each_nested(nla_a,
			    info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
			    nla_a_rem)
		if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSLVL) {
			nla_for_each_nested(nla_b, nla_a, nla_b_rem)
				switch (nla_b->nla_type) {
				case NLBL_CIPSOV4_A_MLSLVLLOC:
					if (nla_get_u32(nla_b) >=
					    doi_def->map.std->lvl.local_size)
					     doi_def->map.std->lvl.local_size =
						     nla_get_u32(nla_b) + 1;
					break;
				case NLBL_CIPSOV4_A_MLSLVLREM:
					if (nla_get_u32(nla_b) >=
					    doi_def->map.std->lvl.cipso_size)
					     doi_def->map.std->lvl.cipso_size =
						     nla_get_u32(nla_b) + 1;
					break;
				}
		}
	if (doi_def->map.std->lvl.local_size > CIPSO_V4_MAX_LOC_LVLS ||
	    doi_def->map.std->lvl.cipso_size > CIPSO_V4_MAX_REM_LVLS)
		goto add_std_failure;
	doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size,
					      sizeof(u32),
					      GFP_KERNEL);
	if (doi_def->map.std->lvl.local == NULL) {
		ret_val = -ENOMEM;
		goto add_std_failure;
	}
	doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size,
					      sizeof(u32),
					      GFP_KERNEL);
	if (doi_def->map.std->lvl.cipso == NULL) {
		ret_val = -ENOMEM;
		goto add_std_failure;
	}
	nla_for_each_nested(nla_a,
			    info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
			    nla_a_rem)
		if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSLVL) {
			struct nlattr *lvl_loc;
			struct nlattr *lvl_rem;

			if (nla_validate_nested(nla_a,
					      NLBL_CIPSOV4_A_MAX,
					      netlbl_cipsov4_genl_policy) != 0)
				goto add_std_failure;

			lvl_loc = nla_find_nested(nla_a,
						  NLBL_CIPSOV4_A_MLSLVLLOC);
			lvl_rem = nla_find_nested(nla_a,
						  NLBL_CIPSOV4_A_MLSLVLREM);
			if (lvl_loc == NULL || lvl_rem == NULL)
				goto add_std_failure;
			doi_def->map.std->lvl.local[nla_get_u32(lvl_loc)] =
				nla_get_u32(lvl_rem);
			doi_def->map.std->lvl.cipso[nla_get_u32(lvl_rem)] =
				nla_get_u32(lvl_loc);
		}

	if (info->attrs[NLBL_CIPSOV4_A_MLSCATLST]) {
		if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
					NLBL_CIPSOV4_A_MAX,
					netlbl_cipsov4_genl_policy) != 0)
			goto add_std_failure;

		nla_for_each_nested(nla_a,
				    info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
				    nla_a_rem)
			if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSCAT) {
				if (nla_validate_nested(nla_a,
					      NLBL_CIPSOV4_A_MAX,
					      netlbl_cipsov4_genl_policy) != 0)
					goto add_std_failure;
				nla_for_each_nested(nla_b, nla_a, nla_b_rem)
					switch (nla_b->nla_type) {
					case NLBL_CIPSOV4_A_MLSCATLOC:
						if (nla_get_u32(nla_b) >=
					      doi_def->map.std->cat.local_size)
					     doi_def->map.std->cat.local_size =
						     nla_get_u32(nla_b) + 1;
						break;
					case NLBL_CIPSOV4_A_MLSCATREM:
						if (nla_get_u32(nla_b) >=
					      doi_def->map.std->cat.cipso_size)
					     doi_def->map.std->cat.cipso_size =
						     nla_get_u32(nla_b) + 1;
						break;
					}
			}
		if (doi_def->map.std->cat.local_size > CIPSO_V4_MAX_LOC_CATS ||
		    doi_def->map.std->cat.cipso_size > CIPSO_V4_MAX_REM_CATS)
			goto add_std_failure;
		doi_def->map.std->cat.local = kcalloc(
			                      doi_def->map.std->cat.local_size,
					      sizeof(u32),
					      GFP_KERNEL);
		if (doi_def->map.std->cat.local == NULL) {
			ret_val = -ENOMEM;
			goto add_std_failure;
		}
		doi_def->map.std->cat.cipso = kcalloc(
			                      doi_def->map.std->cat.cipso_size,
					      sizeof(u32),
					      GFP_KERNEL);
		if (doi_def->map.std->cat.cipso == NULL) {
			ret_val = -ENOMEM;
			goto add_std_failure;
		}
		nla_for_each_nested(nla_a,
				    info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
				    nla_a_rem)
			if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSCAT) {
				struct nlattr *cat_loc;
				struct nlattr *cat_rem;

				cat_loc = nla_find_nested(nla_a,
						     NLBL_CIPSOV4_A_MLSCATLOC);
				cat_rem = nla_find_nested(nla_a,
						     NLBL_CIPSOV4_A_MLSCATREM);
				if (cat_loc == NULL || cat_rem == NULL)
					goto add_std_failure;
				doi_def->map.std->cat.local[
				                        nla_get_u32(cat_loc)] =
					nla_get_u32(cat_rem);
				doi_def->map.std->cat.cipso[
					                nla_get_u32(cat_rem)] =
					nla_get_u32(cat_loc);
			}
	}

	ret_val = cipso_v4_doi_add(doi_def);
	if (ret_val != 0)
		goto add_std_failure;
	return 0;

add_std_failure:
	if (doi_def)
		netlbl_cipsov4_doi_free(&doi_def->rcu);
	return ret_val;
}

/**
 * netlbl_cipsov4_add_pass - Adds a CIPSO V4 DOI definition
 * @info: the Generic NETLINK info block
 *
 * Description:
 * Create a new CIPSO_V4_MAP_PASS DOI definition based on the given ADD message
 * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
 * error.
 *
 */
static int netlbl_cipsov4_add_pass(struct genl_info *info)
{
	int ret_val;
	struct cipso_v4_doi *doi_def = NULL;

	if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
		return -EINVAL;

	doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
	if (doi_def == NULL)
		return -ENOMEM;
	doi_def->type = CIPSO_V4_MAP_PASS;

	ret_val = netlbl_cipsov4_add_common(info, doi_def);
	if (ret_val != 0)
		goto add_pass_failure;

	ret_val = cipso_v4_doi_add(doi_def);
	if (ret_val != 0)
		goto add_pass_failure;
	return 0;

add_pass_failure:
	netlbl_cipsov4_doi_free(&doi_def->rcu);
	return ret_val;
}

/**
 * netlbl_cipsov4_add - Handle an ADD message
 * @skb: the NETLINK buffer
 * @info: the Generic NETLINK info block
 *
 * Description:
 * Create a new DOI definition based on the given ADD message and add it to the
 * CIPSO V4 engine.  Returns zero on success, negative values on failure.
 *
 */
static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)

{
	int ret_val = -EINVAL;
	u32 type;
	u32 doi;
	const char *type_str = "(unknown)";
	struct audit_buffer *audit_buf;
	struct netlbl_audit audit_info;

	if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
	    !info->attrs[NLBL_CIPSOV4_A_MTYPE])
		return -EINVAL;

	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
	netlbl_netlink_auditinfo(skb, &audit_info);

	type = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE]);
	switch (type) {
	case CIPSO_V4_MAP_STD:
		type_str = "std";
		ret_val = netlbl_cipsov4_add_std(info);
		break;
	case CIPSO_V4_MAP_PASS:
		type_str = "pass";
		ret_val = netlbl_cipsov4_add_pass(info);
		break;
	}

	audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_ADD,
					      &audit_info);
	if (audit_buf != NULL) {
		audit_log_format(audit_buf,
				 " cipso_doi=%u cipso_type=%s res=%u",
				 doi,
				 type_str,
				 ret_val == 0 ? 1 : 0);
		audit_log_end(audit_buf);
	}

	return ret_val;
}

/**
 * netlbl_cipsov4_list - Handle a LIST message
 * @skb: the NETLINK buffer
 * @info: the Generic NETLINK info block
 *
 * Description:
 * Process a user generated LIST message and respond accordingly.  While the
 * response message generated by the kernel is straightforward, determining
 * before hand the size of the buffer to allocate is not (we have to generate
 * the message to know the size).  In order to keep this function sane what we
 * do is allocate a buffer of NLMSG_GOODSIZE and try to fit the response in
 * that size, if we fail then we restart with a larger buffer and try again.
 * We continue in this manner until we hit a limit of failed attempts then we
 * give up and just send an error message.  Returns zero on success and
 * negative values on error.
 *
 */
static int netlbl_cipsov4_list(struct sk_buff *skb, struct genl_info *info)
{
	int ret_val;
	struct sk_buff *ans_skb = NULL;
	u32 nlsze_mult = 1;
	void *data;
	u32 doi;
	struct nlattr *nla_a;
	struct nlattr *nla_b;
	struct cipso_v4_doi *doi_def;
	u32 iter;

	if (!info->attrs[NLBL_CIPSOV4_A_DOI]) {
		ret_val = -EINVAL;
		goto list_failure;
	}

list_start:
	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE * nlsze_mult, GFP_KERNEL);
	if (ans_skb == NULL) {
		ret_val = -ENOMEM;
		goto list_failure;
	}
	data = genlmsg_put_reply(ans_skb, info, &netlbl_cipsov4_gnl_family,
				 0, NLBL_CIPSOV4_C_LIST);
	if (data == NULL) {
		ret_val = -ENOMEM;
		goto list_failure;
	}

	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);

	rcu_read_lock();
	doi_def = cipso_v4_doi_getdef(doi);
	if (doi_def == NULL) {
		ret_val = -EINVAL;
		goto list_failure;
	}

	ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type);
	if (ret_val != 0)
		goto list_failure_lock;

	nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_TAGLST);
	if (nla_a == NULL) {
		ret_val = -ENOMEM;
		goto list_failure_lock;
	}
	for (iter = 0;
	     iter < CIPSO_V4_TAG_MAXCNT &&
	       doi_def->tags[iter] != CIPSO_V4_TAG_INVALID;
	     iter++) {
		ret_val = nla_put_u8(ans_skb,
				     NLBL_CIPSOV4_A_TAG,
				     doi_def->tags[iter]);
		if (ret_val != 0)
			goto list_failure_lock;
	}
	nla_nest_end(ans_skb, nla_a);

	switch (doi_def->type) {
	case CIPSO_V4_MAP_STD:
		nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVLLST);
		if (nla_a == NULL) {
			ret_val = -ENOMEM;
			goto list_failure_lock;
		}
		for (iter = 0;
		     iter < doi_def->map.std->lvl.local_size;
		     iter++) {
			if (doi_def->map.std->lvl.local[iter] ==
			    CIPSO_V4_INV_LVL)
				continue;

			nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVL);
			if (nla_b == NULL) {
				ret_val = -ENOMEM;
				goto list_retry;
			}
			ret_val = nla_put_u32(ans_skb,
					      NLBL_CIPSOV4_A_MLSLVLLOC,
					      iter);
			if (ret_val != 0)
				goto list_retry;
			ret_val = nla_put_u32(ans_skb,
					    NLBL_CIPSOV4_A_MLSLVLREM,
					    doi_def->map.std->lvl.local[iter]);
			if (ret_val != 0)
				goto list_retry;
			nla_nest_end(ans_skb, nla_b);
		}
		nla_nest_end(ans_skb, nla_a);

		nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCATLST);
		if (nla_a == NULL) {
			ret_val = -ENOMEM;
			goto list_retry;
		}
		for (iter = 0;
		     iter < doi_def->map.std->cat.local_size;
		     iter++) {
			if (doi_def->map.std->cat.local[iter] ==
			    CIPSO_V4_INV_CAT)
				continue;

			nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCAT);
			if (nla_b == NULL) {
				ret_val = -ENOMEM;
				goto list_retry;
			}
			ret_val = nla_put_u32(ans_skb,
					      NLBL_CIPSOV4_A_MLSCATLOC,
					      iter);
			if (ret_val != 0)
				goto list_retry;
			ret_val = nla_put_u32(ans_skb,
					    NLBL_CIPSOV4_A_MLSCATREM,
					    doi_def->map.std->cat.local[iter]);
			if (ret_val != 0)
				goto list_retry;
			nla_nest_end(ans_skb, nla_b);
		}
		nla_nest_end(ans_skb, nla_a);

		break;
	}
	rcu_read_unlock();

	genlmsg_end(ans_skb, data);

	ret_val = genlmsg_reply(ans_skb, info);
	if (ret_val != 0)
		goto list_failure;

	return 0;

list_retry:
	/* XXX - this limit is a guesstimate */
	if (nlsze_mult < 4) {
		rcu_read_unlock();
		kfree_skb(ans_skb);
		nlsze_mult++;
		goto list_start;
	}
list_failure_lock:
	rcu_read_unlock();
list_failure:
	kfree_skb(ans_skb);
	return ret_val;
}

/**
 * netlbl_cipsov4_listall_cb - cipso_v4_doi_walk() callback for LISTALL
 * @doi_def: the CIPSOv4 DOI definition
 * @arg: the netlbl_cipsov4_doiwalk_arg structure
 *
 * Description:
 * This function is designed to be used as a callback to the
 * cipso_v4_doi_walk() function for use in generating a response for a LISTALL
 * message.  Returns the size of the message on success, negative values on
 * failure.
 *
 */
static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg)
{
	int ret_val = -ENOMEM;
	struct netlbl_cipsov4_doiwalk_arg *cb_arg = arg;
	void *data;

	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
			   cb_arg->seq, &netlbl_cipsov4_gnl_family,
			   NLM_F_MULTI, NLBL_CIPSOV4_C_LISTALL);
	if (data == NULL)
		goto listall_cb_failure;

	ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi);
	if (ret_val != 0)
		goto listall_cb_failure;
	ret_val = nla_put_u32(cb_arg->skb,
			      NLBL_CIPSOV4_A_MTYPE,
			      doi_def->type);
	if (ret_val != 0)
		goto listall_cb_failure;

	return genlmsg_end(cb_arg->skb, data);

listall_cb_failure:
	genlmsg_cancel(cb_arg->skb, data);
	return ret_val;
}

/**
 * netlbl_cipsov4_listall - Handle a LISTALL message
 * @skb: the NETLINK buffer
 * @cb: the NETLINK callback
 *
 * Description:
 * Process a user generated LISTALL message and respond accordingly.  Returns
 * zero on success and negative values on error.
 *
 */
static int netlbl_cipsov4_listall(struct sk_buff *skb,
				  struct netlink_callback *cb)
{
	struct netlbl_cipsov4_doiwalk_arg cb_arg;
	int doi_skip = cb->args[0];

	cb_arg.nl_cb = cb;
	cb_arg.skb = skb;
	cb_arg.seq = cb->nlh->nlmsg_seq;

	cipso_v4_doi_walk(&doi_skip, netlbl_cipsov4_listall_cb, &cb_arg);

	cb->args[0] = doi_skip;
	return skb->len;
}

/**
 * netlbl_cipsov4_remove - Handle a REMOVE message
 * @skb: the NETLINK buffer
 * @info: the Generic NETLINK info block
 *
 * Description:
 * Process a user generated REMOVE message and respond accordingly.  Returns
 * zero on success, negative values on failure.
 *
 */
static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
{
	int ret_val = -EINVAL;
	u32 doi = 0;
	struct audit_buffer *audit_buf;
	struct netlbl_audit audit_info;

	if (!info->attrs[NLBL_CIPSOV4_A_DOI])
		return -EINVAL;

	doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
	netlbl_netlink_auditinfo(skb, &audit_info);

	ret_val = cipso_v4_doi_remove(doi,
				      &audit_info,
				      netlbl_cipsov4_doi_free);

	audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_DEL,
					      &audit_info);
	if (audit_buf != NULL) {
		audit_log_format(audit_buf,
				 " cipso_doi=%u res=%u",
				 doi,
				 ret_val == 0 ? 1 : 0);
		audit_log_end(audit_buf);
	}

	return ret_val;
}

/*
 * NetLabel Generic NETLINK Command Definitions
 */

static struct genl_ops netlbl_cipsov4_genl_c_add = {
	.cmd = NLBL_CIPSOV4_C_ADD,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_cipsov4_genl_policy,
	.doit = netlbl_cipsov4_add,
	.dumpit = NULL,
};

static struct genl_ops netlbl_cipsov4_genl_c_remove = {
	.cmd = NLBL_CIPSOV4_C_REMOVE,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_cipsov4_genl_policy,
	.doit = netlbl_cipsov4_remove,
	.dumpit = NULL,
};

static struct genl_ops netlbl_cipsov4_genl_c_list = {
	.cmd = NLBL_CIPSOV4_C_LIST,
	.flags = 0,
	.policy = netlbl_cipsov4_genl_policy,
	.doit = netlbl_cipsov4_list,
	.dumpit = NULL,
};

static struct genl_ops netlbl_cipsov4_genl_c_listall = {
	.cmd = NLBL_CIPSOV4_C_LISTALL,
	.flags = 0,
	.policy = netlbl_cipsov4_genl_policy,
	.doit = NULL,
	.dumpit = netlbl_cipsov4_listall,
};

/*
 * NetLabel Generic NETLINK Protocol Functions
 */

/**
 * netlbl_cipsov4_genl_init - Register the CIPSOv4 NetLabel component
 *
 * Description:
 * Register the CIPSOv4 packet NetLabel component with the Generic NETLINK
 * mechanism.  Returns zero on success, negative values on failure.
 *
 */
int netlbl_cipsov4_genl_init(void)
{
	int ret_val;

	ret_val = genl_register_family(&netlbl_cipsov4_gnl_family);
	if (ret_val != 0)
		return ret_val;

	ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
				    &netlbl_cipsov4_genl_c_add);
	if (ret_val != 0)
		return ret_val;
	ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
				    &netlbl_cipsov4_genl_c_remove);
	if (ret_val != 0)
		return ret_val;
	ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
				    &netlbl_cipsov4_genl_c_list);
	if (ret_val != 0)
		return ret_val;
	ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
				    &netlbl_cipsov4_genl_c_listall);
	if (ret_val != 0)
		return ret_val;

	return 0;
}